Column Density, Kinematics, and Thermal State of Metal-bearing Gas within the Virial Radius of z ∼ 2 Star-forming Galaxies in the Keck Baryonic Structure Survey
Column Density, Kinematics, and Thermal State of Metal-bearing Gas within the Virial Radius of z ∼ 2 Star-forming Galaxies in the Keck Baryonic Structure Survey
复制标题
凯克重子结构巡天 z 〜 2 恒星形成星系维力半径内含金属气体的柱密度、运动学和热状态
DOI：
--
复制
发表时间：
2019
影响因子：
4.9
通讯作者：
A. Shapley
中科院分区：
文献类型：
--
作者：
G. Rudie;C. Steidel;M. Pettini;R. Trainor;A. Strom;C. Hummels;N. Reddy;A. Shapley
我们目前的结果从凯克重子结构调查（KBSS），包括第一次详细测量的柱密度，运动学，和内部能量的含金属气体维里半径（35-100物理千秒差距）的8个星系在z 2。从我们的完整样本的130个含金属的吸收体，我们推断，晕气体是运动学复杂的单，双，和三重离子化的物种。宽O VI和C IV吸收剂检测到的速度类似的低电离气体，但具有非常不同的运动学结构，表明环星系介质（CGM）是多相的。在100千秒差距内，含金属气体的覆盖率很高，包括高度电离的气体，如O vi;然而，通过透镜背景类星体探测的单个星系的观测表明，含金属云的大小很小（除了O vi气体外，所有含金属云的大小都小于400千秒差距）。在晕中发现的金属质量相当大，相当于星际介质中金属质量的25%。气体运动学明确地表明，70%的星系有金属吸收，有一些未结合的金属富集气体，这表明星系风可能通常从z = 2的晕中喷出气体。当建模时，假设具有不同电离势的离子可以起源于单个气体结构内，在CGM吸收剂中检测到显著的热加宽，其主导气体的内能。大约40%的检测到的气体具有在104.5-5.5 K范围内的温度，其中冷却时间很短，这表明CGM是动态的，具有恒定的加热或冷却以产生这种短暂的热相。
We present results from the Keck Baryonic Structure Survey (KBSS) including the first detailed measurements of the column densities, kinematics, and internal energy of metal-bearing gas within the virial radius (35–100 physical kpc) of eight ∼L* galaxies at z ∼ 2. From our full sample of 130 metal-bearing absorbers, we infer that halo gas is kinematically complex when viewed in singly, doubly, and triply ionized species. Broad O vi and C iv absorbers are detected at velocities similar to the lower-ionization gas but with a very different kinematic structure, indicating that the circumgalactic medium (CGM) is multiphase. There is a high covering fraction of metal-bearing gas within 100 kpc, including highly ionized gas such as O vi; however, observations of a single galaxy probed by a lensed background QSO suggest the size of metal-bearing clouds is small (<400 pc for all but the O vi-bearing gas). The mass in metals found within the halo is substantial, equivalent to ≳25% of the metal mass within the interstellar medium. The gas kinematics unambiguously show that 70% of galaxies with detected metal absorption have some unbound metal-enriched gas, suggesting galactic winds may commonly eject gas from halos at z ∼ 2. When modeled assuming that ions with different ionization potentials can originate within a single gaseous structure, significant thermal broadening is detected in CGM absorbers that dominates the internal energy of the gas. Some 40% of the detected gas has temperatures in the range 104.5–5.5 K where cooling times are short, suggesting the CGM is dynamic, with constant heating or cooling to produce this short-lived thermal phase.
登录
查看更多内容
DOI：
10.3847/1538-4357/aac884
发表时间：
2018-03
期刊：
The Astrophysical Journal
影响因子：
--
作者：
J. Stern;C. Faucher-Giguère;J. Hennawi;Zachary Hafen;S. Johnson;D. Fielding
通讯作者：
J. Stern;C. Faucher-Giguère;J. Hennawi;Zachary Hafen;S. Johnson;D. Fielding
DOI：
10.1086/587486
发表时间：
2007-06
期刊：
The Astrophysical Journal Supplement Series
影响因子：
--
作者：
T. Tripp;K. Sembach;D. Bowen;B. Savage;E. Jenkins;N. Lehner;P. Richter
通讯作者：
T. Tripp;K. Sembach;D. Bowen;B. Savage;E. Jenkins;N. Lehner;P. Richter
影响因子：
4.8
作者：
Zachary Hafen;C. Faucher-Giguère;D. Anglés-Alcázar;J. Stern;D. Keres̆;C. Hummels;C. Esmerian;S. Garrison-Kimmel;K. El-Badry;A. Wetzel;T. K. Chan;P. Hopkins;N. Murray
通讯作者：
Zachary Hafen;C. Faucher-Giguère;D. Anglés-Alcázar;J. Stern;D. Keres̆;C. Hummels;C. Esmerian;S. Garrison-Kimmel;K. El-Badry;A. Wetzel;T. K. Chan;P. Hopkins;N. Murray
DOI：
10.3847/1538-4357/ab378f
发表时间：
2018-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
C. Hummels;Britton D. Smith;P. Hopkins;B. O’Shea;Devin W. Silvia;J. Werk;N. Lehner;J. Wise;D. Collins;Iryna S. Butsky
通讯作者：
C. Hummels;Britton D. Smith;P. Hopkins;B. O’Shea;Devin W. Silvia;J. Werk;N. Lehner;J. Wise;D. Collins;Iryna S. Butsky